Question

q.12. which of the following trends correctly matches the periodic pattern?
a) atomic radius ↑ down group, ie ↑ down group
b) atomic radius ↓ across period, metallic character ↓ across period
c) ionization energy ↓ across period, ea ↑ across period
d) metallic character ↓ down group, atomic size ↑ down group

Explanation:

• Atomic radius: Increases down a group (due to addition of electron shells) and decreases across a period (due to increased nuclear charge pulling electrons closer).
• Ionization energy (IE): Decreases down a group (easier to remove electrons as they are farther from the nucleus) and increases across a period (harder to remove electrons due to increased nuclear charge).
• Electron affinity (EA): Generally increases across a period (more attraction for electrons as nuclear charge increases), but has some exceptions.
• Metallic character: Decreases across a period (elements become less metallic as they gain more non - metallic properties) and increases down a group (elements become more metallic).

Answer:

B. Atomic radius ↓ across period, metallic character ↓ across period